1. Field of the Invention
The present invention relates to a rolling stand of the type with tie-rods, having extremely high strength to axial stresses, which makes it possible high-precision nonsymmetrical-profile rolled sections to be obtained.
2. Discussion of the Background
The presently used rolling stands of the type with tie-rods (referred to in the following as "tie-rod rolling stands") are such as to enable also rolled sections with particular contours, such as a double-"T" contours, to be manufactured with very good quality.
However, it should be remarked here that these rolling stands operate very well for rolled sections with symmetrical contour. An example of a tie-rod rolling stand of :he above type is disclosed in detail in European patent No. 0 166 478.
If the contour of the cross-section of the rolled section is nonsymmetrical, for example an "L"-shaped contour, stresses arise which, by being oriented parallel to the axis of the rolling rolls, cannot be easily counteracted.
The axial stresses have a detrimental impact on the whole structure of the rolling stand, causing mutually engaged moving components to undergo wear during the rolling process. Among such mutually moving components, we remind here, for example, the lead nuts or threaded rings installed in the carriers, and those components which perform the task of guiding the movement.
This drawback generates clearances in the rolling stand and can also endanger the dimensional tolerances of the rolled section product which consequently may not meet the requirements.